Drum stop mechanism for rotary duplicating machines



L. A. SMITZ'ER Nov. 5, 1957 DRUM STOP MECHANISM FOR ROTARY DUPLICATING MACHINES 4 Sheets-Sheet 1 Filed May l1, 1953 Nov. 5, 1957 L. A. sMrrzER 2,812,047

l DRUM STOP MECHANISM FOR ROTARY DUPLICATING MACHINES Filed May l1, 1953 4 Sheets-Sheet 2 I r.L

NOV 5 1957 L. A. sMl'rzER n Y l 2,812,047

DRUM STOP MECHANISM FOR ROTARY DUPLICATING MACHINES Filed May 11. 1953 4 Sheeis-Sheet 3 FIE- jZ I Zoals .Zlzzer Nov. 5, 1957 A. sMlTzER 2,812,047

DRUM STOP MECHANISM FOR ROTARY DUPLICATING MACHINES Filed May 11. 1953 4 sheets-sheet 4 FUE. El

INVENTOR ouai? e);

BY 3M, Bam, Vnk,

Mang. Y

ATTORNEYJ)` United States Patent DRUM STOP MECHANISM FOR ROTARY DUPLICATING MACHINES s Louis A. Smtzer, Chicago, Ill., assgnor to Ditto, Incor-l poi-ated, Chicago, Ill., a corporation'of West Virginia y Application May 11, 195s, serial No. 353,986 s claims. (c1. 192-142) This invention relates to an improved drum stop mechanism for rotary duplicating machines.

Duplicating machines may be'designed to operate continuously for what may be termed as straight duplicating, or they may be designed for systems use in which the drum rotates through a single cycle at a time and is vautomatically stopped at the end of each cycle. v-

In the single cycle type of operation. thev drum maybe stopped by mechanical blocking means, or by a non-4 The present positive or non-blocking type of stop means. invention relates to the latter type.

Colpending Levin application Serial No.l 108,741, led

August 4, 1949, now Patent No. 2,645,174 dated July'14,' 'i

1953, shows a non-blocking type of stop means 'which includes an electric clutch and brake mechanism. The arrangement shown in that application requires a rather complicated control circuit which alternately actuates the clutch and brake.

It is an object of the present invention to providefa` duplicating machine having a much simpler control means therefor. i

The present invention contemplates the use of a-mechanical clutch and brake mechanism of the type shown in my co-pending application Serial No. 346,555, iled April 3, 1953, of which this application is a rcontinuation-in-part..

According to the present invention, the non-blocking braking means is actuated by a Weight or spring actuated device which eliminatesthe use of relays in the controlv vide an improved stop mechanisminfwhich the drum may,

be selectively stopped in one of a plurality of positions. Other objects, features and advantages will become apparent as the description proceeds. k

With reference now to the drawings, in which like references designate like partsj Fig; 1 is a diagrammatic representation of a preferred embodiment of my invention showing the relationship of the control unit-to the other elements of'a duplication machine;

' Fig. 2 is an elevation vof the control unit shown' in Fig. l; f Fig. 3 isa plan View of the control unit of Fig. 2;`

Fig. 4 is a sectional elevation'taken along the line 4%-4 of Fig. 3; *i y v Fig. 5 is a detailed sectionl taken along line 5-5 of Fig. 4, showing the manner in which the controly rod engages the control ring; 'n Fig. 5 is a detailed view of the cam and'cam actuated switches; Fig. 7 is a wiring diagram;

Fig. 8 is a fragmentary vertical section taken along line 8 8 of Fig. 3; and

Fig. 9 is an enlarged sectional View taken along a gen-Y erally cylindrical plane designated by the line 9 9 of Fig. 8, showing the cooperation between the control ring and its adjacent parts, the solid lines indicating the parts in braked position, and the broken lines indicating the parts in drive position.

The present invention is illustrated as applied Vto a duplicating machine of the Wet process type, although it is equally applicable to certain other types of duplicating machines. As shown in Fig. l, the duplicating machine may include a drum 10, a cooperating pressure roll 11, and a pair of feed rolls 12 and 13, which ycooperate with each other and are disposed in front of the bite of thev drum and pressure roll 10 and 11. y v

The feed rolls are driven intermittently from the drum so that during a portion of the drum revolution as the drumy rotates continuously, the contacting feed rolls are stationary so that the bite of the feed rolls provides a stop against which the leading edge of a copy sheet may be f positioned, thus to secure proper registration. Preferably,

the feed rolls, or one of them, are driven through an overrunning clutch and are positively driven by the drum through only about 70 C. of the drum rotation, corresponding to the angle COD in Fig. l. Thereafter, the feed rolls are dragged by the sheet, due to the provision of the overrunning clutch. An example of one such type of feed roll-drive is shown in Levin application Serial No. 215,440, led March 14, 1951, now Patent No. 2,740,353.

The drum 10 is provided with means for supporting a master Asheet on Vits surface in a given position, such as the master clamp 14.

yThe drum 10 is driven from a motor 15 by means of a belt 16 which engages a pulley 17 fixed to or otherwise associated with the drum 10. The control unit includes a clutch 18, the output element of which is a driving pulley 19, which also engages the belt 16.

- 'Thedrum, pressure roll and feed rolls are mounted in a suitable framework, not shown; the framework of the machine also includes la suitable support 20 for the motor 15 and clutch 18. A bracket 21 is provided for mounting the clutch; the bracketis mounted on a support 20, and the clutch is provided with a flange 22 which is suitably screwed to the bracket 21. The operation of the clutch n is controlled by a control member which is'in the form' of a control ring 23,` shown in Figs. 3 and 5.

' ring 24a and a cooperating driven element 24b.

The clutch 18 is shown and described in detail in the aforesaid c'o-pending application Serial No. 346,555, of which this application is a continuation-impart. As described in said application, the clutch includes a brake The driven element is resiliently urged against a driver 70 by spring 24e. The' brake ring 24a is nonrotatably mounted on flange 22, but is axially displaceable so that it maybe urged into engagement with the driven element 24b to displace the same out of engagement with the driver and to cause the driven element to come to a stop. Axial displacement of brake ring is caused by counterclockwise movement of the control ring 23 from the dotted line position to the solid line position, as shown in Fig. 5. In other words, the brake .ring 24a provides a nonblockin'g braking means which causes the drum to come` to a stop.

As shown in Fig. 8, the driver 70 is pinned to a drive shaft 71 `which is suitably journalled in a supporting sleeve 72,' integrally formed with the flange 22. The driven element 2412, integral with pulley 19, is rotatably mounted onthe drive shaft 71.

The control ring 23 is provided with a plurality'of apertures 75. In-,each aperture, there is disposed a pair of Patented Nov.l5, 1957,

a balls 76, such as ball bearing balls. As shownin Figs. 8 and 9, the control ring 23 is disposed between the flange 22 and the brake ring 24a. These members are provided with groovesto receive theportionsof the balls ,76, which project beyond the contines of the control ring, andat.least one ofthese grooves constitutes acalm `grotwe-so thatthe brake ringu can be displaced forwardly.

In the embodimentshown, the tlangel;V is providedr` with a continuous groove 77 of uniform depth. The,rea,r,

surface of the brake ring 24a is provided with a ,pluralityof cam grooves 78, the depth of which tapersrasshown in Fig. 9.

` Both of the grooved elements, the tlangeA 22andthe,4 brake ring 24a, are stationary, inthe sense-ofbeing;non

rotatable. The control ring 23, on theother hand, isfrortat:A ably mounted on that portion of the supporting sleeve 72, which extends forwardly of,the\ange 22.` Hence, as the...

control ring 203's moved ,in the `counterclockwisedirectiorn from the dotted line position inFigs. and.,9,to the solid...`

line positionuwhich, in Fig.9 is indicatedby anrupward movementLthe right hand ball 76,will rnove:upwardly` irr` the ca m groove and cause kthe brakeringto be..displaced.-:

forwardly, or tothe right, asshown `in Fig.;9.

The ,present invention provides means for actuating. the.`

controlnring so thatthe` drum willbe driven througha, single cycle and then automatically stopped.r Thismeansi includes Aa weightactuated means, a latchfor maintain@ ing theweight actuated` means in an` elevatedposition,

and a drum actuated controlcircuit for. releasing/the;-`

latch.`

Theweight actuated means includesa controlrod 253 which, as shown in Figs. 2 and .4 is slidably .mountediinr Since .themoyement of the controly ring fromfitsdrivmA or dottedtlinepositiom to its braked,.or solidlline position, involves work done againsttheforce4 ofxthe spring\24e,` the mass A,of the weight `27 .providesl a .sourceof Lkinetic energy, totacilitate arapid and certain. operation-ofthe Clutch. Although. othenmeans suchasauspring may.. be

providedior biasing, the control. rod .into `its ibralcedf-posi tion, the, gravity actuated weightZTis preferred due `to-the` kinetic .energy.provided.. i i

Means, are` provided ytolrestore. thecweightand :control rod,-to their elevatedposition .andto.move Athe-controlring 23 from,its.brakedposition` toitsdrive position.- This means, asshownirl Fig..1, comprises a lever-30 which is..pivotally mounted .on thesupport 20.VA 'lfheleveiahasaV rounded end 31;1which engages the-headmofua 'screww3`2@ which takes intothelower end ofthe-controlrodZSLJy As shown inFig.. 2, a lock nut` 33ris provided so that the-position .of. ,the screw p maybe securedly. adjustedg thus the screwand lockinut provide means for. adjusting the-throw ofthe .control rod 25,V

Rubber washers 34mayfbe4 provided to absorbanyA shockincident to the operation. of l the Iweighted' control rod.

A foot treadle35 maybe pivotally secured tothe-.base 36` of rthe machine. Alink. connects the .foot treadletandA thelever` 30 soV thatfthe lever. 30.may.be .conveniently operated.. by the operators foot. A counterfbalancing spring 38;may be providedcsothat the Afoot.treadleSSais` biased into its up position.

In operation, when thefoot-treadle 35 is depressedfthe controLrod .25 and the` weight 3.27 are elevated fint'olthe dotted: line position, as shown in Figs.. 1 and-v5,` `thus initiating the cycle of operation. MeansgareLprovidedato latch the control rod in this elevated positionyforythe, remainder of the cycle `of operation., i

As shown in Fig. 4, the control rod` 25 4isprovirlel with; a slabbed portion 40 on which rides a latch lever 41. The

' considered the normal home position.

lower end of the slabbved portion is provided with a notch 42 into which the latch lever drops when the parts are elevated. The latch lever is pivotally mounted in a forked lug 43 which forms a part of the bracket 21 by means of a pivot pin 44. A spring 45, shown in Figs. 3 and 4, urges the latch lever into engagement with the control rod 25. Another arm of thelatch lever is engaged by the plunger-g46gofa solenoid .47.

Thus, whenthe\.control1rod is elevated by depression of thefoot treadle 3S, lthe spring45 causes the latch lever tovdrop, into thenotchgfthus` maintaining the weight and control vrod in their elevated or drive position. Operation of the solenoidwill, retract ,the latch lever, thereby causing the control rod to ,drop and actuate the non-blocking braking means embodied Ain the clutch 1S.

A control circuit is provided to energize the solenoid 47. The control circuit includes notched cam means 50 which ,rotate with thedrum and.which actuate normally open switches 51 `and `52.. As diagrammatically shown in Fig.- 1thefswitches may be effectively spaced about 909 from4 eachother to theend that a circuit through switchgS-Lwill berclosed-90 ahead of a circuit through switch'SZ,

As shown in Fig.-` 6, the notched cam means 50 may comprisea cam-50azhaving a notch 53, and a cam 50b havinga notch 54.; T hesecams 50a and 50h are coaxially mounted side by side onan extension of the drum shaft 56. By providing a separatecam for each switch, the two lswitches `51fand SZmay be mounted on a common mounting.Y plate 55. The switches are vertically offset from each: other so that'cam 50a engages switch 51, and cam 50bfengagesswitcht52; The cams may be adjustably mounted on-thedrumshaft 56 by means of set screws 57.

The position Au of 4:the drum shown in Fig. 1 may be In this position the master clamp. A14 islreadily accessible so that the master sheetlcan bereadilychanged when the drum is in its home position. Hence, when duplicating on sheets of normal length, the .drum is caused to stop in its home position A.V

However, Vwhen `duplicating upon extra long sheets it is desired to cause thedrum to stop in position B, so that theltrailingedge. of .the mastersheet and the superimposed copyssheet will clear ,the bite `ofthe drum and pressure rolllwand 11. The switch 51 causes the drum to stop in its home position A and the switch SZ causes the drum to` stop infthe extralong sheet position B.

Actually, the camsy 50aand 50b are so adjusted that the arm 58 of switch 5'1fdrops into the notch` 53 about 30 to fpriorto-theutimethat the drum moves into its home position: A; This is `for the reason-that the non-blocking braking means does not abruptly stop the drum; rather, a period of deceleration is required which is measured by the decelerationv angle-BOA. Similarly the cam b is adjusted 'to -providef-a` similar'deceleration angle with respect'lto'position B.'y

The-controlcircuit is shown in Fig. 7. The motor is connected acrossy the power leads 60, 61, and an off and on switch 62isprovidedifor the machine as a whole. The cam switches 51 and 52 are connected in parallel with eachother and each being in series with the solenoid 47. Athree-wayvselector switch 63 is provided to establish aseriescircuit betweenone or the other of the cam switches and the solenoid 47, the circuit comprising these elements beingconnected. across the power leads and 61 and in-parallel. withsthemotor circuit. The selector switchisprovided'.with,three positions, 64, 65 and 66. In position 64, the operation of the solenoid is controlled by the.cam,,switch 51; in position 66, it is controlled by cam svvitchf,52.-` Position :65 is an open circuit position which corresponds to continuous operation.`

Sinceieachrof, 4the cam switchesfis actuated once during each rotation of the drum,the time, or point at which the control rod Z5 is released` can be determined by throwing the selector switch to one extreme or the other. When in position 64, the drum will stop at its home position A. When in position 66, the solenoid will not be energized until the drum approcahes the eXtra long sheet position B. When the selector switch is thrown into position 65, the solenoid will not be energized at all, with the result that the control rod will be maintained in its elevated drive position, and the drum will rotate continuously.

The operation has been described in 'detail in connection with the description of the various parts and subassemblies. To summarize, the driimand the feed rolls are driven by a continuously operating motor through a mechanical clutchand brake device 18, the latter providing a non-blocking clutch action for starting the drum and a non-blocking brake action for stopping it. The mechanism of the clutch is described in detail in my aforementioned co-pending application.

The drum may be stopped either in position A or in position B, depending upon the throw of the selector switch 63. By providing a mechanical non-blocking brake or stop mechanism, I have found that a much smaller deceleration period or angle is required, as contrasted with an electric clutch and brake device.

Assuming that the single cycle operation on short sheets is desired, lirstthe switch 62 is closed; then the selector switch 63 is thrown to position 64. The foot treadle 35 is depressed, which causes the drum to rotate and to come to rest in the A position. In this position, the master sheet can be axed to the drum by the master clamp 14. Subsequent cycles of operation are effected merely by depressing the foot treadle 35 once for each cycle of operation. f

For continuous operation, after the master sheet has been secured to the drum, the selector switch is thrown to position 65. The foot treadle 35 is depressed momentarily; the control rod is latched in its drive position for an indefinite period of time. At the conclusion of the continuous duplicating operation, the drum is stopped by throwing the selector switch into its position 64. This procedure would be followed for comparatively long runs, say 25 to 300 copies.

However, for short runs at continuous operation, it is more convenient for the operator simply to maintain the foot treadle 35 depressed.

For single cycle operation on extra long sheets, the drum is brought into its A position, as above described, for axation of the master sheet. Then the selector switch is depressed and the drum will rotate up to position B. Thereafter, sheets may be individually fed into the bite of the feed rolls 12 and 13, and the foot treadle 35 depressed once for each operation, and the drum will come to rest, in each instance, in position B, in which the trailing edges of the master and copy sheets will be clear of the pressure roll 11.

The present invention requires no relays or low voltage relay circuits, hence the only power consumed by the control circuit is that small amount which is required to energize the solenoid once during each drum revolution. There is no power loss when the drum is stationary. The solenoid 47 may be a 120 volt alternating current solenoid so that it may be connected directly to the standard commercial source of electric power, as shown in Fig. 7.

The disclosure of my aforesaid copending application, Serial No. 346,555, is hereby incorporated, by reference, into this specification, insofar as c-onsistent.

Although I have shown herein only a preferred embodiment of my invention, it will be understood that various changes may be made in the construction shown herein without departing from the spirit of my invention as pointed out in the appended claims.

I claim:

1. A duplicating machine comprising a drum, clamp means on said drum for engaging the leading edge of a master sheet supported on said drum, a pressure roll mounted for cooperation with said drum, a motor for driving said drum, clutch and brake mechanism interposed between said motor and said drum and including a control member movable between drive and stop positions and a springy resisting movement of said control member into said stop position, means forV actuating said control member in order to bring said drum to a stop in a home position in which the trailing edge of said master sheet will clear the bite of said drum and pressure roll, said means including a vertically disposed slidably mounted control rod engaging same, said control rod being weighted to bias the same toward stop position, manually operated means for elevating said control rod into a drive position wherein it displaces said control member into its drive position to initiate a cycle of operation of said drum, latch means for maintaining said control rod in drive position, means to release said latch ymeans including a solenoid, and means controlledkbyY the rotation of said drum for energizing said solenoid during each revolution of said drum so as to bring said drum to a stop in its home position, said weighted control rod providing a source of kinetic energy for displacing said control member against the bias of said spring, and said drum controlled means being operative prior to the time that said drum rotates into its home position so as to accommodate the time consumed by the gravity actuated movement of said control rod and the subsequent period of deceleration incident to the operation of said brake and clutch mechanism.

2. In a duplicating machine having a drum, stop means for said drum, `and control means for actuating said stop means in one of a plurality of angular positions of said drum to cause said drum to come to a stop in one of a plurality of angular positions, said control means comprising cam means rotating with said drum, a plurality of normally open cam switches engaging said cam means, each cam switch being disposed at a different eifective angle with respect to said cam means so that said cam switches will be sequentially operated, a control member for said stop means movable between drive and stop positions, means for actuating said control member including a slid-ably mounted control rod engaging same, means biasing said control rod into its stop position, means latching said control rod in its drive position, electrically actuated means for releasing said latching means, a circuit including said electrically lactuated means and said plurality of cam switches, said cam switches being connected in parallel with each other and each being connected in series circuit with said electrically actuated means, and a multiple position selector switch in said electric circuit for providing connecton between a source of power and one or the other of said cam switches whereby said electrically actuated means may be energized by the operation by one or the other of said cam switches to cause said drum to be stopped in one of a plurality of positions.

3. A duplicating machine as claimed in claim 2 including manually actuated means arranged to engage said control rod to shift the same into its drive position.

4. A duplicating machine as claimed in claim 2 in which said cam means comprises a plurality of axially aligned cams 'arranged side by side to each other, and in which said cam switches are offset one from the other in an axial direction so that each `cam switch engages a different cam.

5. In a duplicating machine having a drum, stop means for said drum, and control means for actuating said stop means in one of a plurality of angular positions of said drum to cause said drum to come to a stop in one of a plurality of angular positions, said control means comprising a cam rotating with said drum, a plurality of normally open cam switches engaging said cam, each cam switch being disposed at a different elective angle with respect to said cam so that said cam switches will be sequentially operated, a vertically disposed slidably mounted weighted control rod for said stop means movable between drive and stop positions and biased into its stop position, means latching said control rod in its drive position, electrically actuated means for releasing said latchi'ng means, a circuit including said electrically actuated means and said Vplurality of cam switches, said c'am switches be# ing connected in parallel with each other and each being connected in series circuit with said electrically actuated means, and a multiple position selector switch in said electric circuit por providing connection between a `source of power and one or the other of said cam switches whereby said electrically actuated means may be energized by the operation of one or the other of said cam switches to .cause said drum to be stopped in one of a plurality of positions.

References Cited in the file of this patent UNITED STATES PATENTS 242,544 Lake June 7, 1881 8 Biggert` May 7, 1918 Pearson Apr. 19, 1921 Sidebottom Sept. 13, 19,32; Newell June 129 19371 Lillquist Oct. `21,1941 Bundy Nov. 2,4, 1942 Andres Nov. 28, A195,0 Hoffman et al. Feb. 13, 1951 Drake May 22, 1951v Carter Dec. 25, 195,1 Levin July 14, 1953I FOREIGN PATENTS France Oct. 6, 1902 

